forked from Minki/linux
22b1908610
Most MMU-based CPUs have a restriction on the setting of the data cache enable and mmu enable bits in the control register, whereby if the data cache is enabled, the MMU must also be enabled. Enabling the data cache without the MMU is an invalid combination. However, there are CPUs where the data cache can be enabled without the MMU. In order to allow these CPUs to take advantage of that, provide a method whereby each proc-*.S file defines the control regsiter value for use with nommu (with the MMU disabled.) Later on, when we add support for enabling the MMU on these devices, we can adjust the "crval" macro to also enable the data cache for nommu. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
62 lines
994 B
ArmAsm
62 lines
994 B
ArmAsm
/*
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* We need constants.h for:
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* VMA_VM_MM
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* VMA_VM_FLAGS
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* VM_EXEC
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*/
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#include <asm/asm-offsets.h>
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#include <asm/thread_info.h>
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/*
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* vma_vm_mm - get mm pointer from vma pointer (vma->vm_mm)
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*/
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.macro vma_vm_mm, rd, rn
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ldr \rd, [\rn, #VMA_VM_MM]
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.endm
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/*
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* vma_vm_flags - get vma->vm_flags
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*/
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.macro vma_vm_flags, rd, rn
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ldr \rd, [\rn, #VMA_VM_FLAGS]
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.endm
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.macro tsk_mm, rd, rn
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ldr \rd, [\rn, #TI_TASK]
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ldr \rd, [\rd, #TSK_ACTIVE_MM]
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.endm
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/*
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* act_mm - get current->active_mm
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*/
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.macro act_mm, rd
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bic \rd, sp, #8128
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bic \rd, \rd, #63
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ldr \rd, [\rd, #TI_TASK]
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ldr \rd, [\rd, #TSK_ACTIVE_MM]
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.endm
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/*
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* mmid - get context id from mm pointer (mm->context.id)
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*/
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.macro mmid, rd, rn
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ldr \rd, [\rn, #MM_CONTEXT_ID]
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.endm
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/*
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* mask_asid - mask the ASID from the context ID
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*/
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.macro asid, rd, rn
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and \rd, \rn, #255
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.endm
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.macro crval, clear, mmuset, ucset
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#ifdef CONFIG_MMU
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.word \clear
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.word \mmuset
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#else
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.word \clear
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.word \ucset
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#endif
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.endm
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